A black man and a white man slug it out in the ring. It might be Marquess of Queensberry rules in a hallowed hall of a major English university, but the playing field is far from level as the privileged pale person appears to get away with bending the rules to beat his Black opponent.

It’s a pertinent reminder that pigment was still a primary prejudice of the Britain of 1947, despite the progressive pose adopted that year of independence for India, ultimately punishing because of the appalling legacy of Partition.

The Black Man being duded in the boxing ring is a king, but not a real king like a Windsor or a Tudor, as the British would have it. Disparagingly, he would be the King of Congo Bongo Land. His name is Seretse Khama and his story is the basis of the drolly titled A UNITED KINGDOM.

Seretse, heir to the throne of Bechuanaland, had the temerity of falling in love with a white woman, Ruth Williams, something quite at odds with everyone but the besotted couple. Her folks were not happy and his tribe took a dim view. The British government was displeased as well as it put a strain on Britain’s relationship with South Africa, a country that bordered Bechuannaland.

Indeed, the Brits, first under Labor and even more strenuously under the Tories, imposed hideous sanctions on Seretse personally to placate the masters of the appalling policy of Apartheid.

After all the rights of a madly in love couple don’t amount to a hill of beans beside gold and uranium.

A UNITED KINGDOM is a truly droll title that underlines the dastardliness of Britain when it came to its handling of colonies and the dismantling of the Empire.

Guy Hibbert who previously penned this years best thriller, Eye in the Sky, delivers another polished screenplay, thrilling in its dusting off a little known historical and political potboiler, an anti segregational romance told intelligently by director Amma Asante, a fine follow up to her other beautiful breaking down the racial barriers historical epic, Belle.

David Oyelowo and Rosamund Pike play the two leads in gorgeously understated performances that are poignant in their dignity, stoicism and grace.

Marvellous hiss the villain veracity is achieved by Jack Davenport and Tom Felton as English Establishment figures frightfully fulsome in their effete colonialism.

Seretse and Ruth persevered against the persecution of their so called Protectorate and went on to found a democratic republic, Botswana, to replace the former Bechuannaland.

Fittingly this film is released the year Botswana celebrates fifty years since its inception, a half century that has seen the country emerge as one of the success stories of modern Africa.

A UNITED KINGDOM opens in cinemas on Boxing Day.